Search results for "Coupling"
showing 10 items of 1862 documents
Density distributions in the $B$ meson
2016
We report on a two-flavor lattice QCD study of the axial, charge and matter distributions of the $B$ meson and its first radial excitation. As our framework is the static limit of Heavy Quark Effective Theory (HQET), taking their Fourier transform gives access to several form factors at the kinematical point $q^2=0$. Moreover they provide some useful information on the nature of an excited state, i.e. a radial excitation of a quark-antiquark bound state or a multihadron state.
Supporting data of: Hydrography and food distribution during a tidal cycle above a cold-water coral mound
2022
This file contains the raw data and data analyses scripts to: Hydrography and food distribution during a tidal cycle above a cold-water coral mound Evert de Froe, Sandra R. Maier, Henriette G. Horn, George A. Wolff, Sabena Blackbird, Christian Mohn, Mads Schultz, Anna-Selma van der Kaaden, Chiu H. Cheng, Evi Wubben, Britt van Haastregt, Eva Friis Moller, Marc Lavaleye, Karline Soetaert, Gert-Jan Reichart, Dick van Oevelen. Deep Sea Research Part I: Oceanographic Research Papers, 2022, ISSN 0967-0637, https://doi.org/10.1016/j.dsr.2022.103854. Abstract: Cold-water corals (CWCs) are important ecosystem engineers in the deep sea that provide habitat for numerous species and can form large cora…
Metabolic aspects of the rhythmogenesis inAplysia pacemaker neurons
1973
Completely isolatedAplysia pacemaker neurons were used to investigate mechanisms of endogenous electrical rhythmicity. This preparation allows the study of pure pacemaker activity free from synaptic, ephaptic and/or humoral influences from the surrounding cells. The effect of some substances quite different in their mode of biochemical action were tested: sodium iodoacetate, phloridzin, dinitrophenol, heavy water, and ouabain. Each of these substances suppressed the spontaneous spike activity without any marked depolarizing or hyperpolarizing effect. Spontaneous spike activity of the neurons silenced after addition of one of these substances reappeared after addition of glucose. The restori…
Noninvasive monitoring of polymer curing reactions by dielectrometry
2011
A microwave sensor system for the noninvasive monitoring of the curing process of a thermoset material placed inside a metallic mold is described. The microwave sensor is designed as an open-ended coaxial resonator with a curved surface adapted to the mold inner shape. The analysis of the microwave resonator comprises a recently developed method for deembedding the effect of coupling network in overcoupled resonators, so the range of permitted measurements encompass both low and high dielectric losses of polymeric materials. Results show that noninvasive, continuous monitoring of the microwave dielectric properties of the thermoset material can be performed in real time, allowing one to che…
Iron-Catalyzed Cross-Coupling Reactions of Alkyl Grignards with Aryl Chlorobenzenesulfonates
2021
Aryl sulfonate esters are versatile synthetic intermediates in organic chemistry as well as attractive architectures due to their bioactive properties. Herein, we report the synthesis of alkyl-substituted benzenesulfonate esters by iron-catalyzed C(sp2)–C(sp3) cross-coupling of Grignard reagents with aryl chlorides. The method operates using an environmentally benign and sustainable iron catalytic system, employing benign urea ligands. A broad range of chlorobenzenesulfonates as well as challenging alkyl organometallics containing β-hydrogens are compatible with these conditions, affording alkylated products in high to excellent yields. The study reveals that aryl sulfonate esters are the m…
New high piezoelectric coupling PLuNT binary system ceramics
1999
Abstract The new (1 − x)Pb( Lu 1 2 Nb 1 2 ) O 3 − x PbTiO 3 binary system ceramics in the interval 0 0.49). The morphotropic region extends over the interval x = 0.38–0.49, the concentration ratio M:T ≅ 1 corresponds to x = 0.41. The maximum values of the electromechanical coupling coefficients k p = 0.663, k t = 0.481, k 31 = 0.355 of (1 − x)PLuN-xPT ceramics were attained in compositions PLuNT 59/41 (T m = 353 °C) near the morphotropic phase boundary (MPB). The PLuNT system, having large values of electromechanical coupling and the highest T m (> 350 °C) among binary Pb(B′,B″)O 3 -PT perovskites may be favorable for piezoelectric sensors and actuators, and may have an interest as promisin…
Magnetic and electronic phase transitions probed by nanomechanical resonators
2020
The reduced dimensionality of two-dimensional (2D) materials results in characteristic types of magnetically and electronically ordered phases. However, only few methods are available to study this order, in particular in ultrathin insulating antiferromagnets that couple weakly to magnetic and electronic probes. Here, we demonstrate that phase transitions in thin membranes of 2D antiferromagnetic FePS3, MnPS3 and NiPS3 can be probed mechanically via the temperature-dependent resonance frequency and quality factor. The observed relation between mechanical motion and antiferromagnetic order is shown to be mediated by the specific heat and reveals a strong dependence of the Néel temperature of…
Direct Measurement of Electron-Phonon Coupling with Time-Resolved ARPES
2020
Time- and angular- resolved photoelectron spectroscopy is a powerful technique to measure electron dynamics in solids. Recent advances in this technique have facilitated band and energy resolved observations of the effect that excited phonons, have on the electronic structure. Here, we show with the help of ab initio simulations that the Fourier analysis of the time-resolved measurements of solids with excited phonon modes enables the determination of the band- and mode-resolved electron-phonon coupling directly from the experimental data without any additional input from theory. Such an observation is not restricted to regions of strong electron-phonon coupling and does not require strongl…
Time-Resolved Coherent Anti-Stokes Raman Scattering of Graphene: Dephasing Dynamics of Optical Phonon.
2017
We report dynamics of the G-mode in graphene probed with time-resolved coherent anti-Stokes Raman scattering measurements. By applying BOXCARS excitation geometry with three different excitation wavelengths, various nonlinear processes can be selectively detected due to energy and momentum conservation and temporal sequence of the pulses. The Raman signal due to resonant coherent excitation of the G-mode shows exponential decay with lifetime of ∼325 ± 50 fs. This decay time is shorter than expected based on the line width of the G-mode in the Raman spectrum. We propose that the unexpectedly short dephasing time is a result of dynamic variation of nonadiabatic coupling of the photoexcited el…